EP0379488B1

EP0379488B1 - Device for keeping a bag mouth open and holding the bag against a vertical surface or a pole

Info

Publication number: EP0379488B1
Application number: EP88906960A
Authority: EP
Inventors: Norman Blair
Original assignee: Individual
Current assignee: Individual
Priority date: 1987-08-20
Filing date: 1988-08-05
Publication date: 1994-07-13
Anticipated expiration: 2008-08-05
Also published as: GB2208787B; AU2137088A; EP0379488A1; GB8817730D0; GB8719643D0; WO1989001441A1; DE3850666D1; US5082219A; ES2011490A6; GB2208787A

Abstract

A device (10) which holds the mouth of a bag open and may hold the bag against a vertical surface or to a pole, comprises an elongate belt (11) which is formed into an annular member by use of sleeves (12) and (13) which are attached to the ends of the belt and enable the belt to overlap on itself and the diameter of the device or annular member to be varied. A bag mouth is pulled up through the center of the annular member and the bag's mouth circumference is wrapped over the annular member circumference. The annular member diameter is then increased and the bag clings to the member. The annular member with bag fitted can be held to a vertical surface by a spring clip or to a pole by a spring clip which may be adjusted up or down the pole, the pole being partially pushed into the ground or other stable surface.

Description

The present invention relates to a device for retaining a bag mouth open, and is especially but not exclusively for application with bin bags.
When depositing material into a bag, it is inconvenient to continually hold the mouth of the bag open. This function may be fulfilled by placing the bag inside a rigid cylinder such as a bin and folding the bag over the rim, but a bin is neither portable, nor can it's mouth size by varied to accommodate different sizes of bags.
A plastic belt is disclosed in U.S. Patent Specification No. 3,627,243 for use with paper bags and which has to have a separate clamping member which must be manually displaced to lock the belt in position and can only be used with the bag mouth located outwardly thereof and not folded thereover such that the belt may fall out of the mouth and is difficult to position apart from being less easy to us.
An object of the present invention is to provide a means to help readily and automatically retain open the mouth of bags of various mouth diameters.
According to the present invention, there is provided a device to retain the mouth of a bag open comprising an elongate belt having sufficient flexibility to bend over on itself to form an annular belt of annulus shape with both ends of the belt overlapping each other, and being of sufficient stiffness to be self-containing or self-supporting in any variation of annulus diameter, and at least one sleeve-like holding and securing means for releasably and engageably holding at least one of said ends adjustably to the belt and having a portion by which the one end of the belt is connected thereto and defining a through passage in which an intermediate portion of the belt is held adjacent to said connected and, said intermediate portion being held slidable in said through passage, and being securable in position by securing means, characterized by the feature that the holding means includes said securing means as a portion thereof and is such that, with the periphery of the mouth of the bag folded over the annular belt, the diameter of the annulus can be varied after the mouth of the bag is folded thereover by moving at least one end along the belt relative to the other end to expand to press against the bag such that the material thereof stretches and grips the annular belt, the mouth of the bag being circumferentially held by said annular belt being secured in a position of adjustment by abutment surfaces of said securing means of the holding means; and that said holding and securing means are without an outward or external projection or projections beyond the sleeve which would damage the bag material and said securing means being such as to be capable of operating or being operable without damage to the bag material or without impediment thereby when said bag is folded over the annular belt and so as to securably engage or be engageable with said intermediate portion of the belt by relative displacement between said securing means and the belt such that said abutment surfaces retainably engage said intermediate portion of the belt in said through passage.
Also according to the present invention, there is provided a method of holding the mouth of a bag open, comprising providing a device having a resilient and/or flexible elongate belt of sufficient stiffness as to support the bag and provide a self-locking effect, said belt being bent over on itself to form an annulus with overlapping ends held in position by means of at least one releasable jamming sleeve means secured to one belt portion and with said jamming sleeve means having a belt portion extending therethrough and being without any outward projection which would damage or act as an impediment to said bag material when folded over the annulus; characterized by the step of disposing the open end of the bag within or around the device and relative to the device then folding a peripheral portion of the bag outwardly and downwardly over the device or inwardly over and downwardly over the device, expanding said device outwardly until it places the folded over peripheral portion or the outer bag wall under circumferential tension so as to stretch such and interengage the device with the peripheral portion or outer bag wall and such that the device automatically locks or jams itself or is manually activated through the bag material to secure against contraction by the reactive pressure from said circumferential tension of the peripheral portion.
According to another aspect of the present invention a spiked pole which may be pushed into the ground to act as a support pole for the annular member with a spring clip. The spring clip may be adjusted with reference to its position on the pole by means of the application of hand pressure to the clips surfaces and thereby adjusting the height of the annular member from the ground.
The device may be used to locate a bin bag with a bin by resting on the rim thereof.
The length of band or belt should be such that there is sufficient overlap in the circumference of the closed loop in its likely position of use i.e. relative to the circumference of bag with which it is to be used, so that the loop has a tendency to lock or stick sufficiently to prevent contraction of the loop under the compressive reactive action of the material of the bag against which the loop has been expanded. The "self-locking" phenomena or jamming or sticking may be considered as a result of the created curvature of the belt which, apart from possibly causing increased friction of the belt portions against each other, importantly causes an inclination of the portion of the belt in the passage or passages of the sleeve or sleeves and the outwardly exerted pressure by the belt portions therein against the walls of the sleeve passages. It is believed the belt tends to jam in position of use because of its inclination in the passage of the sleeve(s) or other holding means relative to the central axis thereof because of the pressure exerted by the free end of the belt in its sleeve passage which tilts the sleeve and acts to jam the belt. Thus the dimensioning of the width and thickness of the belt, the length of the belt and the width and thickness of the passage(s) through the sleeve(s) is of importance. Furthermore, the belt portions should not be separated too much in the sleeves but rather the surfaces outside should abut.
The locking passages of the sleeves have shoulder or other closure means at one end to prevent incorrect insertion in the wrong direction whilst otherwise are of the same dimension as the sliding passage. It will be appreciated that whilst free sliding of the belt when in flat straight condition is possible, very little clearance should exist so that with sufficient overlapping of the belt in the annulus, sufficient curvature occurs as to increase the frictional effect of the band portions in contact with each other and with the sliding passage(s) surfaces and/or of the inclination of the belt in the sliding passages of the sleeves and/or tilting of the sleeves by the free ends of the belt as a result of their location so as to produce the necessary self-locking or temporary jamming in the operative position and diameter. Preferably the material of the belt is polypropylene whilst that of the sleeves is plastics material such as nylon. The belt material is to be sufficiently resilient as well as flexible whilst being sufficiently stiff as to be self-supporting when held at one edge and when the bag is being filled.
The exterior surfaces of the sleeves should be smooth and all corners rounded so as to be streamlined and thus not snag or tear the bag material i.e. to permit sliding against the bag in the operative position. The pressure of the belt against the walls of the sliding passages as a result of the resilient effect of the belt material is of significant effect also.
The walls of the sleeves against which the belt portions abut in the locking position of use are sufficiently stiff as not to be deformed and thus act to restrain sliding movement of the belt in the locking condition. Each sleeve is preferably provided with a central dividing wall defining a sliding through-passage for the belt and a locating recess for the belt end with belt end engaging means preferably integrally formed of plastics material.
The invention will be described further by way of example, with reference to the accompanying drawings, in which:

Fig. 1 is a perspective view of part of a loop device showing a free end of a belt and sleeve of Fig. 2 on an enlarged scale;
Fig. 2 is a plan view of a device for holding the mouth of a bag open and forming an embodiment of the invention;
Fig. 3 is a perspective view of the device of Fig. 2 in position of use retaining open the mouth of the bag;
Fig. 4 is a perspective view of a plastics cylinder having a longitudinal slot and which acts as a handle and base for the loop device;
Fig. 5 is a perspective view of a clip for additionally securing the bag to the loop,
Fig. 6 is a perspective view of a discharge member comprising a twisted strip with a notch and which facilities the removal of matter from a separate, hand-held spike (not shown);
Fig. 7 is a perspective view of a further clip which may help to retain the elongate annular member in a tensioned diameter whilst the bag is fitted.
Fig. 8 is a perspective view of a wall clip and pole clip as alternative support devices for the loop device and bag;
Fig. 9 is a fragmentary perspective view of an elongate annular member when it is fitted to the wall clip of Fig. 8;
Fig. 10 illustrates the device and method for securing the sleeves to the ends of the elongate annular member band;
Fig. 11a, 11b and 11c show various operational stages in the method of use;
Fig. 12 is a schematic illustration of an operational technique;
Fig. 13 is a plan view of a preferred form of sleeve;
Fig. 14 is a cross section on the line X - X of Fig. 13;
Fig. 15 is an inverted plan of the sleeve of Fig. 13;
Fig. 16 is a plan view of an end of the belt for use with the sleeve in Figs. 13 - 15;
Fig. 17 is an end elevation from the direction of arrow A of Figs. 13 and 14; and
Fig. 18 is an elevation from the direction of arrow B.

In accordance with the invention a loop device 10 (Fig.2) for holding open the mouth of a bag comprises an elongate belt 11 wound to form an annulus (annular member or body) as shown, and sleeves 12 and 13 retaining the belt 11 in this annular position and configuration.
The annulus is formed, for example, by firstly sliding first sleeve 12 onto the belt 11 via first end 14 and then mounting the second sleeve 14 on the first end 14 of the belt 11. The second end 15 of the belt 11 is then threaded firstly through the sleeve 13 and thence into sleeve 12 to be secured therein causing the belt 11 to form the annulus (annular body) as shown in Fig. 2, the first sleeve 12 and second sleeve 13 are respectively engaged by the second end 15 and first end 14.
The diameter of the annulus may be varied, and may be increased, for example, by sliding end 14 and sleeve 13 anti-clockwise along the belt 11 with respect to end 15 and sleeve 12. In a similar fashion, the annulus may be decreased by sliding the end 15 and sleeve 12 in the opposite direction to that above. The belt 11 is approximately 2 metres long by 25 mm by 3 - 5 mm thick and is constructed from plastic such as polypropylene or spring steel and any material which will serve the purpose.
As shown schematically in Fig. 3, the mouth of the plastics material bin bag or any type of bag 16 is pulled up through the loop device 10 and left to overhang 19 by about 3 to 4 inches. In use, the mouth of the bag is now stretched by increasing the diameter of the loop device 10 by hand pressure in the directions 28 Fig. 2 and the bag mouth will now remain open for depositing materials therein.
To give a more comfortable hand grip a rubber or plastic handle 16 (Fig. 4) is provided, which is cylindrical and has a curved slot 17 running along its length into which a portion of the loop device 10 tightly fits. As shown in Fig. 3, the mouth of a bag 18 is pulled through the loop device and stretched over the device 10 and the device is then increased in diameter by pressure in directions 28 (Fig. 2). The device 10 will then be self-retaining in this larger diameter. For bags which do not stretch easily a clip or clips 20 (Fig.5) are used to fix the bag 18 to the loop device 10.
For most bags the increased diameter will cause the bag to cling to the loop device 10 and the device will be self-retaining in its largest diameter, but the retention of the larger stretched diameter i.e. when the bag is completely fitted may be facilitated by use of the spring clip 29 (Fig. 7). The mouth of the bag 18 remains open for depositing materials therein, and can be gripped by the handle 16 and transported as required.
The open bin bag 18 Fig. 3 is ideally adapted for use with a spike (not shown) for spearing paper. An arm 21 (Fig. 6) forming a discharge member is provided with a notch 22 so that paper on a spike can be released by pulling the spike along the notch 22.
The arm 21 is formed from a strip, the base 23 of which lies flush with one end of the handle 24 and is fixed thereto by a screw 25 through holes 26 and 27. From the flush base 23, the arm twists so as to extend radially inwards over the open bag mouth and presents the notch 22 for use with the spike. The loop device 10 may be held against a vertical surface before or after the bag is fitted, by means of an adjustable clip 30. (Fig. 8). The loop device 10 sits in this clip as illustrated in Fig. 9. The height of the loop device 10 from the floor or ground may be adjusted by the screw and slot mechanism 31. The loop device 10 may be held against a vertical pole 32 (Fig. 8) which has a pointed lower end and is partially pushed into the ground. The method of holding the annular body on the pole is by a spring clip 33 (Fig. 8) and is the same method as that of it being held in the clip 30 as shown in Fig. 9. The clip may be adjusted with reference to its position on the pole and thereby adjusting the height of the loop device 10 from the ground or floor, by hand pressure being applied to the surfaces of the clip.
Fig. 10 illustrates methods by which the sleeves 12 and 13 may be fitted to tie ends of the elongate belt 11. The elongate belt 11 has a hole 34 and 35 at either end 14 and 15. A projection or spud 36 is provided in the inside of each sleeve 12 or 13 and are designed to engage in the holes 24, 35 and when doing so preventing the sleeve From separating from the elongate belt 11. The spud can either be engaged by using a sleeve as 37 where there is a horizontal split, and both the top and bottom come together to envelope the elongate belt 11 or by using a sleeve as 38 (only bottom section of the sleeve is shown and is sectioned in the horizontal plane) where the elongate belt is pushed horizontally through the sleeve and the spud 36 is on a flexible strip 39 which will move up and down to let the belt engage into the spud, the spud engaging when pressure is applied to force the belt through the sleeve. The vertical movement of the flexible strip on which the spud is mounted is shown by the arrow 40. Sleeve type 38 may be integrally formed with the sliding-through passage for the belt (not shown). Both sleeve type 37 and 38 are self-locking and permanent. An 'eye' may be moulded on the sleeve of either type so as to enable the spring 20 or 29 to be attached to the loop device 10 by means of a cord. The 'eye' is not shown.
Through passages are provided in each sleeve (12, 13) (37, 38) for the through sliding of portions of the belt 11 intermediate the ends (14, 15). Each sleeve also has a recess or passage for receiving an end 14, 15 of the belt 11 which in Fig. 2 the passages are on the outer side of the annulus for end 14 and on the inner side for end 15. The sleeves are shaped and dimensioned so as to permit the sliding relative to the bag material without jamming or damaging such.
The method of combining a loop device with the mouth of a plastics material bag is amplified in Figs. 11a - 11c and Fig. 12 and the stages might be listed as follows :

1. Open out bag and expand Flexi-Bin ring until diameter is slightly smaller than bag mouth diameter.
2. Noting the sleeve positions on ring, bring bag up through, and fold over ring, giving a minimum overlap of 5" - 6"
3. Noting sleeve positions, put fingers of both hands up below Flexi-Bin ring, as Figs. 11a - 11c show, and pull ring to expand. (It is important that pull is in the correct direction - relative to sleeve positions).
4. Turn ring with bag fitted 90 degrees and pull to expand ring again. Ring will now firmly grip the bag.

Whilst the device may be used with advantage simply inside the mouth of a bag with the periphery folded inwards the preferred arrangement of the bag extending through the annulus formed by the device and the periphery of the mouth being folded outwardly over and downardly provides exceptional advantages as regards location and operation and ease of use. The slight deformation or stretching of the folded over portion when the device is expanded thereagainst enhances the gripping action and provides exceptional advantages.
A further preferred embodiment of loop device of the invention is illustrated in Figs. 13 to 18 and is similar to that of Fig. 2 and is for use with a polythene bin bag having a diameter of approximately 65.5 cm, the belt is flat being 182 cm long, 2.6 cm wide (actually 1 inch wide), is .5 cm (3/6") thick and of generally rectangular cross section. The sleeves are dimensioned approximately 3.2 cm (1¼") by 3.2 cm (1¼") by 1.75 cm (¾") deep. The sleeves are identical but oppositely and reversely disposed in use and have sliding or through passages in which the belt slides are 3.1 cm (1¼") long, 2.7 cm (1.1/16") wide and .6 cm (¼") deep. In the sleeves, the separating wall between the belt portions is 2.5 mm (1/16"). In use with the loop device holding the bag mouth open, the device has an approximate 137.1 cm. (4'6") circumference with adjacent edges of the sleeves being spaced at 15.85 cm (6¼") measured circumferentially over the overlapped portion of the belt. The opposite edges are spaced at 83.8 cm (2'9") circumferentially over the non-overlapping belt portion. The loop device does not appear to start self-locking until the adjacent sleeve edges are approximately 25.4 cm (10") apart circumferentially over the overlapping part of the annulus.
In Figs. 13 to 18 a preferred embodiment of sleeve is illustrated comprising two identical moulded plastics members 40 (only one shown) each having a through passage 41 for sliding of belt 11 which are dimensioned relative to each other so that as the loop diameter decreases and the inner end 15 of belt 11 pivots and tilts sleeve 40, the upper run of belt 11 becomes inclined relative to the longitudinal axis of the passage 40 (exaggerated in Fig. 14) so that jamming or "automatic partial locking" occurs especially at edges 42, 43 sufficient to prevent collapsing of the loop by the pressure of the bag acting thereagainst but such that special manipulation readily removes the jamming effect.
A lower passage 45 has a shoulder or reduced cross sectional portion 46 at one end which prevents the end of belt 11 passing through and enables the projection 48 which is supported by an arm 47 made so as to be resiliently flexible by side slits 51 and an end slot 52 so that when there is inserted the end of belt 11 which has a cooperating aperture therein, such deflects slightly and then springs-back to retain the end in position by virtue of the shaping of of a ramp like portion of triangular cross-section.
The external edges and corners of the sleeves 40 are rounded or "streamlined" to slide relative to the bag material without damaging such or jamming.
Each sleeve 40 has a central dividing wall 44 and lower, locating passage 45 which has a reduced cross-sectional area at one end 46 as a stop for belt end 15 which is identical to outwardly located belt end 14 (see Fig.2) in that it is in this arrangement provided with a rectangular through passage 47 which is engageable with a resiliently mounted ratchet-like, retaining projection 48 in passage 45. Projection 48 is formed by a ramp-like portion in the passage 45 with an inclined surface 49 and a perpendicular face 50 which locates in passage 47 of belt 11. The projection 48 is resiliently displaceable by having two slots 51 formed either side leading to passage 52 so that the resilience of the material of sleeve 40 may become effective because of the weakening thereby.
As will be apparent from Fig. 14 the other end 14 of belt 11 has an identical sleeve 40 located thereon but in inverted and reversed disposition so that belt 11 is oppositely inclined and jams against edges opposite to edges 42, 43.
Various modifications may be made without departing from the present invention. For example partial self-jamming or locking to resist the compressive forces of the bag material etc. in use may be achieved by toothing on the belt and ratchet-like members in the sleeves (or vice versa) or other manually operable securing and release means may be provided such as to be operable when the bag material is folded over the device and through the material and such as not to damage or jam with the bag material in use e.g. a double acting push button area with belt securing and release action operable through the material may be used.
As a minor modification, the belt and sleeves may have a curved or arcuate cross-section so as to provide an outwardly facing channel in which a rubber or other elastic band or belt may be located stretched to hold the bag, folded thereover, in position on the annulus or ring. Also, of different inventive concept, is a similar but non-adjustable ring of curved cross-section or other shape to hold an elastic ring in position and substantially of a diameter over which the bag mouth may just be folded to he held in position by the elastic ring - suitable clips and supports may be provided as desired.
In Fig. 12, the fingers of the right-hand are placed between the ring and bag and pull on the double side of the ring. It is of considerable importance for the device according to the present invention to have the ability or capability to expand after the bag mouth has been wrapped over it.

Claims

A device (10) to retain the mouth of a bag (18) open comprising an elongate belt (11) having sufficient flexibility to bend over on itself to form an annular belt of annulus shape with both ends (14,15) of the belt overlapping each other, and being of sufficient stiffness to be self-containing or self-supporting in any variation of annulus diameter, and at least one sleeve-like holding and securing means (12,13:37,38:40) for releasably and engageably holding at least one of said ends adjustably to the belt and having a portion (36,37:49,50) by which the one end of the belt is connected thereto and defining a through passage (37',41) in which an intermediate portion of the belt (11) is held adjacent to said connected end (14,15), said intermediate portion being held slidable in said through passage (37',41), and being securable in position by securing means, characterized by the feature that the holding means (12,13:37,38:40) includes said securing means (37',40-43) as a portion thereof and is such that, with the periphery (19) of the mouth of the bag (18) folded over the annular belt (11), the diameter of the annulus can be varied after the mouth of the bag is folded thereover by moving at least one end (14,15) along the belt relative to the other end (15,14) to expand to press against the bag (18) such that the material thereof stretches and grips the annular belt, the mouth of the bag being circumferentially held by said annular belt being secured in a position of adjustment by abutment surfaces (42,43) of said securing means (37',40-43) of the holding means (12,13:37,38:40); and that said holding and securing means (12,13,37,37',38,40-43) are without an outward or external projection or projections beyond the sleeve (12,13:37,38:40) which would damage the bag material and said securing means being such as to be capable of operating or being operable without damage to the bag material or without impediment thereby when said bag is folded over the annular belt and so as to securably engage or be engageable with said intermediate portion of the belt by relative displacement between said securing means and the belt such that said abutment surfaces retainably engage said intermediate portion of the belt in said through passage.
A device as claimed in claim 1, wherein each holding and securing means (37',40-43) is a sleeve (12,13) which is located on one end (14/15) of the belt and each sleeve (12,13) is designed such that an end (14,15) of the belt is contained in the sleeve by a non-return ratchet pawl (48,49,50), or is fixed by a pin (36) or by enveloping the belt or is moulded as part of the belt.
A device as claimed in claim 1 or 2, wherein means (33) are provided for holding the annular belt (11) in a horizontal plane to a pole (32), the pole being vertical and partially pushed into the ground or other stable surface and the annular belt being held to it by means of a spring clip (33) which can move up or down the pole when hand pressure is applied to the top or bottom surfaces of part of the clip, the clip staying fixed securely on the pole of its own accord due to the elasticity of the spring clip when the pressure is not being applied and when the annular belt is attached.
A device as claimed in any of claims 1 to 3, in which each holding means (40) is streamlined by having smooth exterior surfaces and rounded corners and with the securing means (41,42,43) being contained wholly within the sleeve (40) so as not to prevent sliding of the belt and sleeve against the material of a bag and/or so as not during such sliding action to damage the material of a bag when folded thereover preferably when the bag is within the ring and the edge is folded outwardly and downwardly.
A device as claimed in any of claims 1 to 4 in which the holding and securing means (12,13;37,38;40-43) operates such that when the size of annulus of intended use has been reached by increasing the diameter of the annulus with the bag material being folded thereover and the device (10) presses against the bag material to stretch such and to cause it to cling to the annular member (11), the annular belt (11) is automically locked or secured in said position of use to prevent the annulus being reduced in diameter by the reactive compressive force of the bag material and to prevent the disengagement of the device from the bag (18).
A device as claimed in any of claims 1 to 5, in which the intermediate portion of the belt (11) is securable by securing means (37';41-43) which comprises so mounting the belt (11) in said holding means (12,13;37,38;40) and shaping and/or dimensioning the guide passage relative to the belt dimension such that when expanded at the likely position of use, there is relative tilting between the holding and securing means (37';41-43) and the belt (11) to restrict movement of said belt relative to said holding and securing means sufficiently to prevent undesired reduction in diameter by the action of the bag material.
A device as claimed in claim 6 in which said securing means comprises ratchet-like teeth or notches on the belt cooperable with a resiliently deflectable projection (48-50) on the belt guide means or other non-return mechanism or belt securing means as to secure the annular belt in position.
A device as claimed in any of claims 1 to 5 in which the securing means of the holding and securing means comprises a push button mechanism, a bi-stable locking switch means, a wedge-like or other jamming means or deflectable sleeve body portion (48-50) engageable with the belt to hold such in position and manually operable through the bag material whilst being displaceable relative to said material without damaging such or undesirably catching or jamming therewith.
A device as claimed in claim 6, in which the holding and securing means is a sleeve (42) comprising a body having two generally parallel passages (41,45) extending therethrough and separated by a dividing wall (44); one said passage (45) being for receiving one end of the belt and engaging with an aperture therein by means of a resiliently deflectable retaining projection (47), the other said passage (41) having a portion of said belt (11) slideable therethrough and forming said guide passage for acting as said annulus securing means.
A device as claimed in any of claims 1 to 9 in combination with a bag (18) of flexible plastics material.
A device as claimed in at least claim 1, in which the belt is arranged as a ring and two holding means are provided each in the form of a sleeve (12,13) one at each end (14,15) of the belt, in which the mouth of the bag is circumferentially held by said ring in a position of adjustment by securing means of the sleeve; in which each said sleeve and securing means is without an external projection or projections beyond the sleeve which and in which each said sleeve has a first portion defining a passage and in which the one end of the belt is connected and has a second portion which defines said through passage in which the intermediate portion of the belt is held adjacent to said connected end, said intermediate portion being held slidable in said through passage and being securable therein in the expanded condition of the belt by said securing means which is contained wholly within the sleeve; said securing means comprising so mounting the end of the belt in said sleeve and shaping and/or dimensioning the guide passage relative to the belt dimension such that when expanded at the likely position of use a resultant reactive pressure from the circumferential tension of the engaged portion of the bag to cause relative tilting between the sleeve and the belt so as to automatically frictionally restrict movement of said belt relative to said sleeve sufficiently to prevent undesired reduction in diameter by the action of the bag material.
A method of holding the mouth of a bag (18) open, comprising providing a device having a resilient and/or flexible elongate belt (11) of sufficient stiffness as to support the bag and provide a self-locking effect, said belt being bent over on itself to form an annulus with overlapping ends (14,15) held in position by means of at least one releasable jamming sleeve means (12,13;37;40) secured to one belt portion and with said jamming sleeve means having a belt portion extending therethrough and being without any outward projection which would damage or act as an impediment to said bag material when folded over the annulus; characterised by the step of disposing the open end of the bag (18) within or around the device (10) and relative to the device, then folding a peripheral portion of the bag to be then folded outwardly and downwardly over the device or to be folded inwardly over and downwardly over the device, expanding said device outwardly until it places the folded over peripheral portion (19) or the outer bag wall under circumferential tension so as to stretch such and interengage the device with the peripheral portion or outer bag wall and such that the device automatically locks or jams itself or is manually activated through the bag material to secure against contraction by the reactive pressure from said circumferential tension of the peripheral portion.